This invention relates to a brush, more particularly to a brush with extendible and retractable bristle elements.
The improvement of this invention is directed to the conventional brush shown in FIG. 1, which includes a lower housing 90, a bristle plate 91, a crank type rotary lever 92, a hair-separating needle 93, and an upper housing 94. The bristle plate 91 has a plurality of bristle elements 95. A guide plate 97 has a plurality of guide holes 971 in alignment with the bristle elements 95 and the bristle holes 901 of the lower housing 90. A position-limiting plate 98 is connected securely to the guide plate 97 by means of four guide posts 981, so as to move the bristle plate 91 between the guide plate 97 and the position-limiting plate 98. Two springs 982 (only one is shown) interconnect two sides of the bristle plate 91 and two sides of the guide plate 97, so as to push the bristle plate 91 upward to press against the position-limiting plate 98, thereby retracting the bristle elements 95 into the housing unit, which consists of the lower housing 90 and the upper housing 94. The rotary lever 92 is placed between the bristle plate 91 and the position-limiting plate 98 at one end thereof and confined by a curved retainer 902 within the notch 903 of the lower housing 90 at the other end thereof. In use, the rotary lever 92 is rotated to push the bristle plate 91 downward by the crank portion 922 of the rotary lever 92, so as to extend the bristle elements 95 from the housing unit 90, 94 through the guide holes 971 of the guide plate 97 and the bristle holes 901 of the lower housing 90. At the same time, the tongue 961 of a push lever 96 engages within the groove 921 of the rotary lever 92, so as to prevent the rotation of the rotary lever 92. A short spring 962 biases the tongue 961 to engage within the groove 921. When the user desires to separate two tangled strands of hair, the push lever 96 is actuated to disengage the tongue 961 from the groove 921 of the rotary lever 92, so that the springs 982 retract the bristle elements 95 into the housing unit 90, 94. A rotary knob 99 includes a fixed pinion 991 meshing with the rack 931 of the needle 93. Actuation of the rotary knob 99 extends the needle 93 from the hole 941 of the upper housing 94. The inner end 1001 of a generally zigzag pawl member 100 is pushed to catch the serrated portion 932 of the needle 93 by spring action, so as to prevent the movement of the needle 93 relative to the housing unit 90, 94. When the outer end 1002 of the pawl member 100 is pressed, the pawl portion 1001 separates from the needle 93, so that the needle 93 retracts into the housing unit 90, 94 by the action of a long spring 933 which is sleeved on the needle 93. The release of the outer end 1002 of the pawl member 100 locks the needle 93 relative to the housing unit 90, 94. It is easy for this complicated brush to malfunction.